The present invention relates generally to methods and systems for production of hydrocarbons from various subsurface formations.
Steam-assisted gravity drainage (SAGD) is used to recover hydrocarbons from a subsurface formation from fields where the hydrocarbons from a subsurface formation is extremely dense or has high viscosity. In this regard, steam from a horizontal wellbore is used to decrease the viscosity and to cause the hydrocarbons from a subsurface formation to drain into a second horizontal wellbore.